1^0 SPONTANEOUS RISE OF HOT LIE IN A PUMP. 



fact with which 1 find myself embarrassed. You have often 



/ obliged your correspondents with disquisitions or investigations 



in cases like the present. Whether this may lead to any useful 



result beyond the mere fact, I know not : I am sure you will 



admit it to be curious ; and if you have not seen it, I beg you 



will take the trouble to do so, and oblige me, and your other 



readers, with your opinion of its cause. 



Description of Some time ago I visited an extensive soap manufactory, in 



a boiler t;on- which there were several large boilers, each capable of holding: 



taing soap and ^ ^ ^ r , ■ , t , 



lie ; a tun or soap. One of them was m a state to have the lie 



drawn off from beneath the soap, which formed a fluid mass 

 between three and four inches thick, above a depth of perhaps 

 and a copper ^^^^ ^^^^ °^ ^'^- ^ speak from memory throughout. There 

 pump to was a wooden back or vessel on one side to receive the lie, and 



lie from be. ^ ^^pper pomp was lowered down into the boiler from a situa- 

 neatli the soap, tion in which it had hung suspcflded above by a tackle. I think 

 the barrel of the pump might be about four inches in diameter, 

 terminating in a small copper cistern at top, with a spoutof about 

 three inches bore, proceeding from one side of the cistern close to 

 its bottom. I do not remember whether the pump was primed 

 or not, but I think not, and suppose it may have had metallic 

 ' valves, and perhaps a hempen packing, instead of leather, which 

 could not be used with soap lie. The pump was, I doubt not, 

 lowered so as to rest on the bottom of the boiler, for it could 

 not else have been steady — and a workman began to pump. 

 When the hot 1^^® lie came out of the spout in a stream which did not half 

 Jie was first fill the bore, and it fell at no considerable distance from the 

 e/Fect vvas not ^pout. During the whole experiment the soap and the lie \q 

 remarkable, the boiler appeared level and motioHiess, neither circulating 

 nor showing any other sign of its high temperature, the soap at 

 but after a few top preventing even the steam from appearing. But after a 

 strokes it very few strokes the lie dashed out of the spout with a sudden 



t'aneoualy, ' i^oise, and flew to the opposite side of the receptacle in a stream 

 hot, smoking, frothy, and filling the bore of the spout. The 

 workman left off pumping, and the stream continued with un- 

 ceasing violence and rapidity. I was astonished, gnd stood gaz- 

 ing at this striking effect, my mind being engaged with a mix- 

 ture of wonder at the phenomenon and puzzle at its continu- 

 and continued '"g» when the apparent cause had ceased to act. But after a 

 considerable time, I turned to the assistaats, and asked, " how it 



was 



